我在界面里添加了ScrollView 为什么不会滚动啊

Cocos2d-x
#1 
    // 加载背景
Layout *ui = (Layout*)(GUIReader::getInstance()->widgetFromJsonFile("SelectHeroUI/SelectHeroUI.json"));
this->addChild(ui);

// 滚动层
ScrollView *heroScrollView = ScrollView::create();
Size scrollSize(680,360);
heroScrollView->setSize(scrollSize);
Size innerSize(scrollSize.width,scrollSize.height*2);
heroScrollView->setInnerContainerSize(innerSize);
Point scrollPoint(114,221);
heroScrollView->setPosition(scrollPoint);
heroScrollView->setDirection(ScrollView::Direction::VERTICAL);
heroScrollView->setInertiaScrollEnabled(true);
heroScrollView->setBounceEnabled(true);
ui->addChild(heroScrollView);

// 添加元素
int width=130,height=122,count=5,row=0,column=0;
for (int i=0;i<30;i++)
{
    HeroItem *item = HeroItem::create();
    row = i/count;
    column = i%count;
    Point point(column*width+75,innerSize.height-row*height-55);
    item->setPosition(point);
    heroScrollView->addChild(item);
}
#2

实现CCScrollViewDelegate接口了吗？

#3

没有呀，怎么实现呀

#4

参考 testcpp示例下的extensions/CocostudioGUITest/GUI Dynamic Create Test/gui ScrollViewTest

#5

需要实现它的delegate中实现的委托函数的方法
void scrollViewDidScroll(ScrollView* view);
void scrollViewDidZoom(ScrollView* view);
void scrollViewMoveOver(ScrollView* view);